118 resultados para Robô móvel não-holonômico


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Objective: A history of childhood trauma is common in individuals who later develop psychosis. Similar neuroanatomical abnormalities are observed in people who have been exposed to childhood trauma and people with psychosis. However, the relationship between childhood trauma and such abnormalities in psychosis has not been investigated. This study aimed to explore the association between the experience of childhood trauma and hippocampal and amygdalar volumes in a first-episode psychosis (FEP) population. Methods: The study employed an observational retrospective design. Twenty-one individuals, who had previously undergone magnetic resonance imaging procedures as part of the longitudinal Northern Ireland First-Episode Psychosis Study, completed measures assessing traumatic experiences and were included in the analysis. Data were subject to correlation analyses (rand rob). Potential confounding variables (age at FEP and delay to scan from recruitment) were selected a priori for inclusion in multiple regression analyses. Results: There was a high prevalence of lifetime (95%) and childhood (76%) trauma in the sample. The experience of childhood trauma was a significant predictor of left hippocampal volume, although age at FEP also significantly contributed to this model. There was no significant association between predictor variables and right hippocampal volume. The experience of childhood trauma was a significant predictor of right and total amygdalar volumes and the hippocampal/amygdalar complex volume as a whole. Conclusions: The findings indicate that childhood trauma is associated with neuroanatomical measures in FEP. Future research controlling for childhood traumatic experiences may contribute to explaining brain morphology in people with psychosis.

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Venom has only been recently discovered to be a basal trait of the Anguimorpha lizards. Consequently, very little is known about the timings of toxin recruitment events, venom protein molecular evolution, or even the relative physical diversifications of the venom system itself. A multidisciplinary approach was used to examine the evolution across the full taxonomical range of this similar to 130 million-year-old clade. Analysis of cDNA libraries revealed complex venom transcriptomes. Most notably, three new cardioactive peptide toxin types were discovered (celestoxin, cholecystokinin, and YY peptides). The latter two represent additional examples of convergent use of genes in toxic arsenals, both having previously been documented as components of frog skin defensive chemical secretions. Two other novel venom gland-overexpressed modified versions of other protein frameworks were also recovered from the libraries (epididymal secretory protein and ribonuclease). Lectin, hyaluronidase, and veficolin toxin types were sequenced for the first time from lizard venoms and shown to be homologous to the snake venom forms. In contrast, phylogenetic analyses demonstrated that the lizard natriuretic peptide toxins were recruited independently of the form in snake venoms. The de novo evolution of helokinestatin peptide toxin encoding do-mains within the lizard venom natriuretic gene was revealed to be exclusive to the helodermatid/anguid subclade. New isoforms were sequenced for cysteine-rich secretory protein, kallikrein, and phospholipase A 2 toxins. Venom gland morphological analysis revealed extensive evolutionary tinkering. Anguid glands are characterized by thin capsules and mixed glands, serous at the bottom of the lobule and mucous toward the apex. Twice, independently this arrangement was segregated into specialized serous protein-secreting glands with thick capsules with the mucous lobules now distinct (Heloderma and the Lanthanotus/Varanus clade). The results obtained highlight the importance of utilizing evolution-based search strategies for biodiscovery and emphasize the largely untapped drug design and development potential of lizard venoms. Molecular & Cellular Proteomics 9:2369-2390, 2010.

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We investigate the Nash equilibria of game theoretic models of network formation based on explicit consent in link formation. These so-called “consent models” explicitly take account of link formation costs. We provide characterizations of Nash equilibria of such consent models under both one-sided and two-sided costs of link formation. We relate these equilibrium concepts to link-based stability concepts, in particular strong link deletion proofness.

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This essay is intended as a self-reflective, auto-critique of the ‘social accounting community’. The essay is directed at the academic community of accountants concerned with social accounting. This `community' is predominantly concerned with English language accounting journals and is preoccupied with the social and environmental practices of the larger private sector organisations. The essay is motivated by a concern over our responsibilities as academics in a world in crisis and a concern that social accounting is losing its energy and revolutionary zeal. This community's social accounting endeavours have taken place in almost complete ignorance of the activities and developments in non accounting communities and, in particular, developments in the public and third sectors. The essay reaches out to the public and third sector work and literature as an illustration of one of the ways in which ‘our’ social accounting can try to prevent itself from becoming moribund.

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Transcriptional regulators, such as SoxS, RamA, MarA, and Rob, which upregulate the AcrAB efflux pump, have been shown to be associated with multidrug resistance in clinically relevant Gram-negative bacteria. In addition to the multidrug resistance phenotype, these regulators have also been shown to play a role in the cellular metabolism and possibly the virulence potential of microbial cells. As such, the increased expression of these proteins is likely to cause pleiotropic phenotypes. Klebsiella pneumoniae is a major nosocomial pathogen which can express the SoxS, MarA, Rob, and RamA proteins, and the accompanying paper shows that the increased transcription of ramA is associated with tigecycline resistance (M. Veleba and T. Schneiders, Antimicrob. Agents Chemother. 56:4466-4467, 2012). Bioinformatic analyses of the available Klebsiella genome sequences show that an additional AraC-type regulator is encoded chromosomally. In this work, we characterize this novel AraC-type regulator, hereby called RarA (Regulator of antibiotic resistance A), which is encoded in K. pneumoniae, Enterobacter sp. 638, Serratia proteamaculans 568, and Enterobacter cloacae. We show that the overexpression of rarA results in a multidrug resistance phenotype which requires a functional AcrAB efflux pump but is independent of the other AraC regulators. Quantitative real-time PCR experiments show that rarA (MGH 78578 KPN_02968) and its neighboring efflux pump operon oqxAB (KPN_02969_02970) are consistently upregulated in clinical isolates collected from various geographical locations (Chile, Turkey, and Germany). Our results suggest that rarA overexpression upregulates the oqxAB efflux pump. Additionally, it appears that oqxR, encoding a GntR-type regulator adjacent to the oqxAB operon, is able to downregulate the expression of the oqxAB efflux pump, where OqxR complementation resulted in reductions to olaquindox MICs.

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While the BBC had been broadcasting television Science Fiction productions from as early as 1938, and Horror since the start of television in 1936, American Telefantasy had no place on British television until ITV’s broadcast of Adventures of Superman (1952-1958) in 1956. It would be easy to assign this absence to the avoidance of popular American programming, but this would ignore the presence of Western and adventure serials imported from the US and Canada for monopoly British television. Similarly, it would be inaccurate to suggest that these imports were purely purchased as thrilling fare to appease a child audience, as it was the commercial ITV that was first to broadcast the more adult-orientated Science Fiction Theatre (1955-7) and Inner Sanctum (1954). This article builds on the work of Paul Rixon and Rob Leggott to argue that these imports were used primarily to supply relatively cheap broadcast material for the new channel, but that they also served to appeal to the notion of spectacular entertainment attached to the new channel through its own productions, such as The Invisible Man (1958-1959) and swashbucklers such as The Adventures of Robin Hood (1955-60). However, the appeal was not just to the exciting, but also to the transatlantic, with ITV embracing this conception of America as a modern place of adventure through its imports and its creation of productions for export, incorporating an American lead into The Invisible Man and drawing upon an (inexpensive) American talent pool of blacklisted screenwriters to provide a transatlantic style and relevance to its own adventure series. Where the BBC used its imported serials as filler directed at children, ITV embraced this transatlantic entertainment as part of its identity and differentiation from the BBC.